Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
  • B29C44/34—Auxiliary operations
  • B29C44/3442—Mixing, kneading or conveying the foamable material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
  • B29C44/34—Auxiliary operations
  • B29C44/36—Feeding the material to be shaped
  • B29C44/46—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length
  • B29C44/50—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length using pressure difference, e.g. by extrusion or by spraying
  • B29C44/507—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length using pressure difference, e.g. by extrusion or by spraying extruding the compound through an annular die
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/022—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the choice of material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/285—Feeding the extrusion material to the extruder
  • B29C48/288—Feeding the extrusion material to the extruder in solid form, e.g. powder or granules
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/285—Feeding the extrusion material to the extruder
  • B29C48/29—Feeding the extrusion material to the extruder in liquid form
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D1/00—Treatment of filament-forming or like material
  • D01D1/06—Feeding liquid to the spinning head
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/24—Formation of filaments, threads, or the like with a hollow structure; Spinnerette packs therefor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
  • B29C48/05—Filamentary, e.g. strands
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
  • B29C48/07—Flat, e.g. panels
  • B29C48/08—Flat, e.g. panels flexible, e.g. films
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
  • B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
  • B29C48/10—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels flexible, e.g. blown foils
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/0005—Condition, form or state of moulded material or of the material to be shaped containing compounding ingredients
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/04—Condition, form or state of moulded material or of the material to be shaped cellular or porous

Definitions

• a porous hollow filament or porous film composed of a cellulose ester polymer or polysulfone polymer is often used for fluid treatments, for example, liquid treatments such as filtration, ultrafiltration, and dialysis, and gas treatments such as a separation of gases.
• porous products are prepared mainly by wet shaping processes such as wet spinning, melt shaping processes such as melt spinning, and plasticizing melt shaping processes using a plasticizer, such as plasticizing melt spinning.
• the plasticizing melt spinning of a cellulose ester polymer or in the case of the plasticizing melt spinning for forming a porous hollow filament by using a poor solvent, a complicated process is adopted in which the cellulose polymer is first pulverized, the pulverized cellulose ester polymer is mixed and impregnated with a plasticizer, if necessary together with the poor solvent, by a blender or the like, the mixture is taken out and is heated and melt-extruded by a single-screw extruder, the extrudate is cooled and out into a pelletized chip, the chip is dried by a hot air drier, the dried chip is heated and melted again, the melt is spun into a hollow filament by a spinning machine, the filament is cooled and solidified, the plasticizer or the plasticizer and poor solvent are removed by extraction with water or the like, and the formed porous yarn is wound.
• the twin-screw extruder used in the present invention has a vent zone, and preferably, after a powder of an organic polymer and a liquid additive are mixed in a kneading zone of the extruder to form a substantially liquid mixture, this substantially liquid mixture is deaerated under a reduced pressure in the vent zone and then fed to a kneading and compressing zone. Where deaeration is not carried out in the vent zone, preferably the starting material is sufficiently dried before being supplied to the twin-screw extruder.
• D stands for the diameter of the element or screw and the groove depth is the vertical distance from the top of the screw thread to the bottom of the trough.
• the twin-screw extruder means used in the present invention is provided with a vent downstream of the kneading zone, and the substantially liquid mixture formed in the kneading zone is deaerated in the vent portion.
• the deaeration is carried out when little evaporation of the liquid additive has occurred.
• Elevation of the pressure in the extruding zone is necessary to make it possible to feed the liquid mixture containing the polymer under pressure and stably perform the shaping operation, and generally the pressure in the extruding zone is preferably 10 to 100 kg/cm2G. If the pressure exceeds 100 kg/cm2, the vent is increased and simultaneously, the polymer temperature is elevated by a generation of heat due to the shear stress, resulting in an increased coloration of the polymer. Accordingly, too high a pressure is not preferred. In contrast, if the pressure is too low, feeding of the liquid becomes difficult due to conduit resistance, and a stable shaping is difficult at a pressure lower than 10 kg/cm2. Therefore, too low a pressure is not preferred. Note, preferably a filter means for removing solids having an undesirable affect on the shaping operation is disposed before the extruding zone.
• the twin-screw extruder may be either a lateral or longitudinal type, but in view of the stability of feeding of the powder, lateral type twin-screw extruder is preferred.
• the organic polymer used in the present invention in the case of the plasticizing melt shaping, there can be mentioned heat-decomposing polymers and heat-curable polymers.
• heat-decomposing polymers in the case of the plasticizing melt shaping, there can be mentioned cellulose acetates such as cellulose diacetate and cellulose monoacetate, and cellulose esters such as cellulose nitrate and cellulose propionate.
• cellulose acetate is advantageous for use.
• thermoplastic polymer As the organic polymer used in the melt shaping in the present invention, there can be mentioned a thermoplastic polymer, and as specific examples, there can be mentioned polyesters, polyamides, polyolefins, polystyrene, polycarbonate, polyvinyl chloride and polysulfones. These thermoplastic polymers also can be used in the above-mentioned plasticizing melt shaping.
• a pore-forming agent is used as the additive in the melt shaping in the present invention.
• polyethylene glycol polypropylene glycol, glycerol, phthalic acid esters and fatty acid esters.
• the present invention is characterized in that the powder of the organic polymer and the liquid additive are separately fed to the feed zone of the twin-screw extruder.
• the feed ratio between the powder and the liquid additive is such that the additive is fed in an amount of at least 30 parts by weight per 100 parts by weight of the organic polymer, and the upper limit of the amount of the additive is preferably about 300 parts by weight per 100 parts by weight of the organic polymer. Note, to determine the characteristic properties of the porous shaped article, this ratio should be adjusted to a certain value within this range.
• a mixing and heating zone i.e., a kneading zone of the twin-screw extruder
• the cellulose diacetate flake and polyethylene glycol were mixed and heated at 180 to 240°C to form a plasticized melt.
• the melt was vacuum-deaerated under (b) mmHg a in a vent zone of the twin-screw extruder, and in a kneading and compressing zone of the twin-screw extruder, the melt was kneaded at a temperature of (c)°C and simultaneously compressed under a pressure of (d) kg/cm2G.
• the melt was fed to a spinning nozzle and extruded from a double-tube nozzle together with nitrogen forming a hollow portion to form a hollow filament by spinning.
• the rotation number of the twin-screw extruder was adjusted to 200 rpm, and the average residence time of the polymer was adjusted to 170 seconds.
• the results are shown in Table 1.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Textile Engineering (AREA)
• Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
• Separation Using Semi-Permeable Membranes (AREA)
• Artificial Filaments (AREA)
• Extrusion Moulding Of Plastics Or The Like (AREA)

Applications Claiming Priority (4)

Publications (4)

Family

ID=26365591

Family Applications (1)

Country Status (4)

Cited By (2)

Families Citing this family (12)

Family Cites Families (34)

• 1988
  • 1988-09-28 JP JP63240723A patent/JP2528169B2/ja not_active Expired - Lifetime
  • 1988-09-28 US US07/250,420 patent/US4913864A/en not_active Expired - Fee Related
  • 1988-10-12 EP EP88116889A patent/EP0316571B2/de not_active Expired - Lifetime
  • 1988-10-12 DE DE3888094T patent/DE3888094T3/de not_active Expired - Fee Related

Also Published As

Similar Documents

Legal Events